Cioffi, Gino

Abstract Background Global incidence for brain tumors varies substantially without explanation. Studies correlating radon exposure and incidence are inconclusive. Particulate pollution has been linked to increased tumor incidence. Particulates may disrupt the blood-brain barrier allowing intracranial exposure to oncogenic radon. We investigated the relationship between exposure to residential radon, particulate pollution, and brain tumor incidence in the United States (US). Methods County-level median radon testing results and annual air quality index values were obtained and divided into tertiles. Counties without both values were excluded. Four groups of counties were generated: high particulate/high radon (high/high), high/low, low/high, and low/low. Using incidence data from the Central Brain Tumor Registry of the US (provided by CDC’s National Program of Cancer Registries and NCI’s SEER), annual age-adjusted incidence rates (AAAIRs) by group were generated by behavior. Incidence rate ratios were calculated to examine for significant differences (α = .05). Poisson regression accounting for possible confounders was conducted. Results Counties with available data included 83% of the US population. High/high exposure was significantly associated with increased AAAIR of all non-malignant tumors (up to 26% higher, including most meningiomas) even after accounting for potential confounders. An increased AAAIR was noted for all malignant tumors (up to 10% higher), including glioblastoma, but was negated after accounting for demographic/socioeconomic differences. Conclusions We present the first report suggesting increased non-malignant brain tumor incidence in regions with high particulate and radon exposure. These findings provide insight into unexplained variation in tumor incidence. Future studies are needed to validate these findings in other populations.

Abstract INTRODUCTION The NIH Revitalization Act, implemented 29 years ago, set to improve the representation of women and minorities in clinical trials. In this study, we investigate the progress made in neuro-oncology in all phase therapeutic clinical trials for neuro-epithelial central nervous system tumors in comparison to their demographic-specific age-adjusted disease incidence and mortality. METHODS Registry study of all published clinical trials for World Health Organization (WHO) defined neuro-epithelial CNS tumors between January 2000 and December 2019. Study participants for trials were obtained from PubMed and ClinicalTrials.gov. Population-based data from the CBTRUS for incidence analyses. SEER-18 Incidence-Based Mortality data was used for mortality analysis. Descriptive statistics, Fisher exact, and c2 tests were used to analyze the data. RESULTS Among 662 published clinical trial articles representing 49, 907 accrued participants, 62.5% of study participants were men and 37.5% were women (P< 0.0001) representing a mortality specific over-accrual for men (P= 0.001) and under-accrual for women (P= 0.001). Whites, Asians, Blacks, and Hispanics represented 91.7%, 1.5%, 2.6%, and 1.7% of trial participants. Compared with their US cancer mortality, Blacks (47% of expected mortality, P=.008), Hispanics (17% of expected mortality, P< .001) and Asians (33% of expected mortality, P< .001) were underrepresented compared with Whites (114% of expected mortality, P< .001). CONCLUSIONS Nearly 30 years since the Revitalization Act, minorities and women are consistently underrepresented when compared with their demographic-specific incidence and mortality in therapeutic clinical trials for neuroepithelial tumors. This study provides a framework for investigating cancer clinical trial accrual and offers guidance regarding workforce factors associated with enrollment of vulnerable patients.